In this paper, we propose a robust output-feedback model predictive control (MPC) design for a class of open-loop stable systems, having non-vanishing output disturbances, hard constraints and linear-time invariant model uncertainty. Integral action is included in the proposed design by utilizing a linear estimator for both the output disturbance and the system state. The main distinction from previous work on robust MPC design (with integral action) is that we establish robust convergence in the face of both imperfect state information and dynamic model uncertainty.